One way of destroying documents to preserve the confidentiality thereof is to cut the same into narrow strips in a process known commonly as shredding. A specific known way of shredding is achieved with circular knives with a number of circular knives and spacers being stacked on a shaft and drawn together with two such stacked shafts being meshed together in order to form a cutting head. Paper guides or combs are used to guide the paper into the cutting heads and to lead the paper out for purposes of discharge. A very significant problem which occurs with this general type of apparatus is that pieces of paper get caught between the meshing rotating members or between the combs and one of the rotating members, whereby the machinery is jammed and sometimes irreparably damaged.
U.S. Pat. No. 2,554,114 shows one type of shredding machine in which interdigitated circular cutting members are employed. This equipment is generally of the type described above and is susceptible of being jammed by the trapping of paper pieces therein.
U.S. Pat. No. 2,894,697 (M. H. Panning et al) also shows a shredder in which rotating members are provided with interdigitated cutting elements which are also susceptible of being jammed by paper pieces being trapped therein.
U.S. Pat. No. 3,396,914 (A. J. Liebman) also shows a machine for disintegrating paper and other waste materials. The machine uses interdigitated rotatable cutting members which may also be jammed in the manner referred to hereinabove.